Centrifugal absorbtive thermodynamic apparatus and method

ABSTRACT

AMMONIA AND WATER ARE ROTATED IN A ROTARY ENCLOSURE. AMMONIA GAS IS DRIVENOUT OF THE WATER. DIFFERENTIAL ACTION OF THE CENTRIFUGAL FORCE ON THE LIQUID AND THE GAS IS USED TO TRANSPORT THE GAS AND WATER WITHOUT USE OF A MECHANICAL PUMP. THE GAS AND THE WATER ARE PUMPED THROUGH THE ROTOR TOGETHER. WITH THE GAS FLOW AIDING IN PUMPING THE LIQUID.

F. w. KANTOR v CENTRIFUGAL ABSORBTIVE THERMODYNAMIC APPARATUS AND METHOD Feb. 2, 1971 Filed July 18, 1969 INVENTOR. zkffliR/C/K llZ/Kwvrve United States Patent ()fice 3,559,419 Patented Feb. 2, 1971 US. Cl. 62-101 13 Claims ABSTRACT OF THE DISCLOSURE Ammonia and water are rotated in a rotary enclosure. Ammonia gas is driven out of the water. Difierential action of the centrifugal force on the liquid and the gas is used to transport the gas and water without use of a mechanical pump. The gas and the water are pumped through the rotor together, with the gas flow aiding in pumping the liquid.

This invention relates to thermodynamic apparatus and methods utilizing centrifugal force for compression and movement of working fluids. This application is a continuation-in-part of US. patent application Ser. No. 608,- 321, filed on Jan. 10, 1967, now Pat. No. 3,456,454, granted July 22, 1969.

In my copending US. patent application Ser. No. 608,- 323, filed J an. 10, 1967, there is disclosed a novel centrifugal refrigeration and heating apparatus and method in which gas and/or liquids are rotated in a sealed closedloop conduit in a rotary enclosure. One object of the present invention is to provide a highly advantageous adaptation of the basic principles disclosed in my copending patent application to absorbtive refrigeration and heating systems. Another object of the present invention is to provide such apparatus and methods which give good heat transfer and are highly efficient, with apparatus which is compact, simple, and has a minimum of moving parts. A further object is to provide such apparatus which is capable of operating in locations, such as in space, where there is no way to use a natural gravitational field to provide the necessary separation of gases and liquids. A still further object is to make use of a thermodynamic cycle whose operation is especially advantageous in rotary systems with low rotational speeds.

The drawings and description that follow describe the invention and indicate some of the ways in which it can be used. In addition, some of the advantages provided by the invention will be pointed out.

In the drawings:

FIG. 1 is a cross-sectional, partially schematic view of one embodiment of the present invention;

FIG. 2 is a partially schematic cross-sectional view, to a reduced scale, taken along line 2-2 of FIG. 1; and

FIG. 3 is a partially broken-away view, also to a reduced scale, taken along line 3-3 of FIG. 1.

The device shown in FIG. 1 includes a rotor indicated generally at with a shaft 12 mounted in appropriate bearings (not shown) and rotated by a motor 14 about a rotational axis 16.

The rotor 10 includes an annularly-shaped liquid chamber 18 which contains a quantity of liquid 19 in which a refrigerant is absorbed. The liquid 19 flows from chamber 18 to an outer annular separation chamber 20 with a dome-shaped inner wall 88 through a passageway 26 which exits near the outermost portion of chamber 20.

A condensing chamber 22 is located near the axis 16 of the rotor 10. A slender conduit30 interconnects the separator (generator) chamber 20 and the condensing chamber 22, with the inlet opening 31 of conduit being located at the innermost wall of chamber 20. The innermost end 33 of conduit 30 exits into a chamber 82 which is positioned inside chamber 22. An opening 90 in chamber 82 permits gas to escape into chamber 22. Water leaves chamber 82 through another conduit 80 at the farthest point in chamber 82 from the axis 16. Conduit 80 extends through the rotor wall at point 81, and is arranged in a spiral coil on the outside of the rotor 10 (see FIG. 3). The tube 80 then re-enters the housing at 83 to conduct water from chamber 82 back to chamber 18 where it again absorbs ammonia gas.

The right-hand portion of chamber 22 is frusto-conical in shape and has a plurality of metal blades 53 extending radially outwardly from its surface. The ammonia gas which contacts the walls of the frusto-conical portion is cooled and condensed and flows to the left in the chamber. The right hand portion of the frusto-conical portion is broken away and not shown in the drawings. The blades 53 serve a dual purpose. Blades 53 enhance the cooling of the ammonia gas in chamber 22, and also blow air over the tube 80 to cool it.

An evaporation chamber 24 is positioned to the left of chambers 18 and 22. An elongated tube 32 extends to a point adjacent the left wall of chamber 24. A member 36 is attached to the left end of tube 32 to hold the tube in place. A series of ridges 40 are positioned on the inside surface of the outermost wall 37 of evaporator chamber 24 in order to collect and hold evaporating liquid ammonia along the wall 37 for efficient cooling.

The tube 32 has an outwardly-extending bent portion 87 which serves as a trap to prevent gas from flowing back through tube 32 into chamber 22. Tube has a similar bend to prevent gas from flowing in it. The chamber 22 has a very small hole 91 at the shaft 12 to permit a light bulfer gas such as hydrogen to escape from the chamber 22 during start-up.

The liquid and gas are sealed hermetically in the rotor 10. As a specific example, the absorbent liquid is Water, and the refrigerant is ammonia mixed with hydrogen. The hydrogen is not absorbed in the water to any significant degree, and acts as a buffer gas. However, it should be understood that other known combinations of fluids used in absorbtion heating and refrigeration systems may be used in accordance with the principles of the present invention.

The operation is by an absorbtion cycle: ammonia vapor at low partial pressure, in a butler gas (hydrogen), is absorbed by cold water in chamber 18. This solution flows radially outward, and is heated in chamber 20, evolving gaseous ammonia. Ammonia and hot water move radially inward, with ammonia condensing at high partial pressure in chamber 20, and flowing through duct 32 to evaporate in chamber 24. Water returns to chamber 18 through cooling duct 80, and the cycle repeats. Suitable heat exchange means are provided.

In greater detail, the operation of the device shown in FIG. 1 is as follows: The rotor 10 is accelerated to a constant speed of rotation by a motor 14. The liquid in chamber 20 is heated through fins 49 secured to the outer wall 51 of chamber 20. The gaseous ammonia in chamber 22 is cooled and condensed, and the liquid in tube 80 is cooled by the air from fan blades 53, as well as from several supporting fins 52. Ambient air is cooled by contact with fins 54 on the outer wall of the evaporator chamber 24.

The liquid flowing outwardly through tube 26 is heavily laden with ammonia. The heating of the liquid in separation chamber 20 causes the ammonia to be separated from the liquid. As the ammonia evolves from the liquid,

it moves inwardly towards the innermost, dome-shaped wall 88 of chamber and thence towards inlet 31 of conduit 30. Upon entering conduit 30, the gaseous ammonia entraps the water in conduit and forces it towards chamber 22. The ammonia gas cools and condenses as it strikes wall in chamber 22. The liquid ammonia is represented by reference numeral in FIG. 1.

The interior diameter of conduit 30 is small enough to ensure that gas bubbles ordinarily will fill the entire cross-sectional area of the tube and thus will carry slugs or segments of liquid through the conduit. The foregoing process will be repeated frequently, with the result that liquid is transported radially inwardly through duct 30.

When water emerges from outlet 33 of conduit 30, it enters chamber 82 but is prevented from entering chamber 22 by centrifugal force. Instead, the water collects on the radially outermost interior wall of chamber 82 where it enters conduit 80. Gas leaves chamber 82 through an outlet 90 which is located and shaped so as to prevent any escape of splashing water into chamber 22. Water flow through spiral conduit 80 is created by centrifugal force. The exposure of this conduit to moving ambient air cools the water before it enters chamber 18, and thus enables it to absorb more ammonia.

The liquid ammonia emerges from tube 32 and, if it does not evaporate immediately, collects in annularlyshaped pools 38 between the ribs 40. The fins 54 conduct heat to the liquid 38 contacting the outer wall 37 of chamber 24, and thus evaporate the liquid. The gaseous ammonia then moves in the convectively circulating buffer gas to the right and towards the surface of the water 19 in chamber 18, as indicated by the dashed arrows 59, where it again is absorbed.

As is well known, the temperature of the water should be maintained at a low level in order to keep its ammonia absorbtion rate high. The temperature of the liquid 19 is kept low by means of the flow of cold ammonia vapor and cold buffer gas.

Thermal insulation is provided between the chambers 18 and 20, between the liquid in chamber 20 and the wall of conduit 26, and around the portion of conduit 30 which passes through chamber 18. This insulation protects against undesired thermal transfer between the conduits so insulated from one another. Similarly, insulation is provided at other places shown in the drawings, in order to prevent undesired heat transfer.

The addition of heat in separation chamber 20 preferably is accomplished by forcing hot gasses in the direction indicated by the arrow 48 between a pair of annular stationary baffle members shown at 62 and 64, The bafiie member 62 preferably is made of thermal insulating material so as to minimize heat transfer to the fins 54. Each of the radial fins 49 has a plurality of peripherally-spaced holes 59 (see FIG. 2). The heated air flows inwardly between guides 62 and 64, passes from one fin to the next through holes 59, and then flows outwardly after it has exchanged its heat with the fins. Another annular bafile 66 at the right edge of the chamber 20 guides the warm air outwardly from the fins 49 and prevents interference with the air thrown off by fins 52 and 53.

As is best shown in FIG. 3, fins 52 are shaped spirally so as to pump air through them rapidly and enhance heat transfer. Of course, the fins 52 and 53 can have any other shape desired. Also, as is well known, heat transfer can be further enhanced by using liquids instead of gases as the cooling media. For the sake of clarity in the drawings, the fins 53 are not shown in FIG. 3.

Each of the fins 54 has a plurality of punched-out sections 68 which form fan blades. These fan blades draw in ambient air to be cooled, cool the ar, and blow the air to the left where it may be used for refrigeration as desired. It should be understood that the device may be used advantageously for heating as well as refrigeration simply by using the heat given off by fins 52 and 53 for heating purposes.

All conduits are shown in FIG. 1 in a diagrammatic form for the purpose of clarifying the explanation of the operation of the invention. The actual preferred construction is shown in FIG. 2.

FIG. 2 shows a radial separator plate 84 extending from the inner wall to the outer wall of chamber 20.

Plate 84 is located between the outlet of conduit 26 and the inlet of conduit 30 so that the ammonia-laden water travels the maximum circumferential distance before exiting from chamber 20. This enhances heat transfer to the liquid. Similarly, a separator plate 86 extends radially from the outer wall of chamber 18 inwardly to slightly closer to the axis than the rotational water level and separates the outlet of conduit from the inlet of conduit 26 so that the water travels the maximum circumferential distance in chamber 18. This advantageously maximizes the time of contact between the liquid and the gas coming from chamber 24 so as to maximize the absorbtion of gas into the liquid.

In order to guide the fiow of ammonia gas towards the inlet to the tube 30, the inner wall 47 of chamber 20 is given a very slight spiral shape; that is, the wall 47 has a gradually decreasing radial distance from the axis 16, with the wall 47 at the inlet to tube 30 being closest to the axis 16. For clarity of presentation in FIG. 2, both plate 86 and the outlet conduit 80 are shown rotated approximately 45 clockwise from their actual positions. It should be understood, of course, that weights should be added to balance the structure if any unbalance occurs due to asymmetrical location of the flow passages and working fluids.

One of the major advantages of the present invention is that the gaseous ammonia in chamber 22 is concentrated (to a high partial presure) without the use of a mechanical compressor, and the liquid is pumped through the system without need for a mechanical pump. The pumping and circulation of the various fiuids are produced by the differential action of centrifugal force upon the liquid in chamber 18 and conduit 26, and the gas and liquid in conduit 30. The volume of gas in conduit 30 usually is very much greater than that of the liquid in the conduit. Thus, the density of the liquid in conduit 26 is significantly greater than that of the gas and liquid in conduit 30, and there is a significant net pressure driving the liquid and gas through the conduit 30.

An advantage of this invention is that positive and reliable pumping of the liquids and gases is provided at all times. Furthermore, the use of a buffer gas makes it possible to operate with essentially just that pressure difference needed to overcome gas friction, because the thermodynamic work is done in the creation and maintenance of different partial gas pressures. Thus the rotor can be driven at a considerably lower speed than has been practical before. Also, the heat transfer surfaces are in contact with liquids, thus greatly increasing the rate of heat flow and permitting a high heat pumping capacity in a relatively small device. Thus, the unit may be made so small that it can be carried as a part of an astronauts space suit or can be used as part of a biological package with an integral cooling system.

Another important advantage is that the device of this invention provides its own substitute for a gravitational field, and yet requires no outside pumping unit. Thus, it can be used where there is no Way to use a gravitational field, for example, in space, or in vehicles in which the alignment of the system with respect to the gravitational field is not constant.

The above description of the invention is intended to be illustrative and not limiting. Various changes or modifications in the embodiments described may occur to those skilled in the art and these can be made without departing from the spirit or scope of the invention as set forth in the claims. For example, among the variations well known in the art are the use of various heat exchange systems to permit the use of what is known as regenerative cooling. Further variations include the use of heat exchange fins as vanes in blowers, in centrifugal or other pumps for liquids, etc.; and the use of many types of heat source (electrical, nuclear, chemical, etc.), either within the rotating system itself or indirectly.

I claim:

1. A'bsorbtive heating and refrigeration apparatus, said apparatus comprising, in combination, a rotor, means for rotating said rotor, first conduit means extending between first and second radial positions with respect to the rotational axis of said rotor for conveying between said positions a first fluid absorbed in a second fluid, means for separating said first fluid in gaseous form from said second fluid, second conduit means extending towards said axis to a third radial position for conveying said gas and said second fluid towards said axis under pressure, means for liquefying said gas at said third position, and third conduit means for conveying said liquefied gas to a fourth radial position, means for adding heat to said liquefied gas at said fourth position and evaporating it, fourth conduit means for conveying the said second fluid from said third position back to said first position, and fifth conduit means between said fourth and first radial positions for passage of said gas evaporated in said fourth radial position.

2. Apparatus as in claim 1 including means for forming gas bubbles in said second conduit means and entrapping portions of said second fluid in said second conduit and carrying the portions of said second fluid to said third chamber.

3. Apparatus as in claim 1 including an annular chamber at each of said first and second positions, the ends of said conduit means extending into said chambers at positions which are separated from one another circumferentially so as to maximize the circumferential flow of liquids in each of said chambers before flowing into the other chamber.

4. Apparatus as in claim 1 in which said first fluid is a refrigerant gas, and including a buffer gas mixed with said refrigerant gas.

-5. Apparatus as in claim 4 in which said refrigerant gas is ammonia and said buffer gas is hydrogen.

6. Apparatus as in claim 1 including a frusto-conical condensing chamber at said third radial position, and a plurality of heat exchanging blades connected to said chamber.

7. Apparatus as in claim 3 in which one of said chambers in said first and second positions surrounds the other, in which the ends of said two conduits entering said outermost chamber are separated by a first separator member extending from the outermost wall to the innermost wall of the outermost chamber, and the ends of said two conduits entering said innermost chamber are separated by a second separator member extending from the outermost wall of said innermost chamber to a position inward from the normal innermost rotational liquid level in the innermost chamber.

8. Thermodynamic apparatus comprising, in combination, a rotor, means for rotating said rotor about an axis, first, second and third chambers carried by said rotor at corresponding first, second and third radial distances from said axis, said second distance being greater than said first and third distances, first conduit means interconnecting said first and second chambers for directing the flow of liquids therebetween, second conduit means intercon-.

meeting said second and third chambers for directing the flow of a gas and liquid therebetween, a fourth chamber within said third chamber for collecting said liquid, third conduit means for returning said liquid to said first chamber, fourth conduit means interconnecting said third andfirst chambers for directing the flow of liquids therebe- 6 tween, and means for conducting heat into said first and second chambers and out of said third chamber.

9. Apparatus as in claim 8 including a liquid in said first and second chambers, a first gas in said chambers, said first gas being easily absorbed by said liquid, and a second gas in said first chamber not easily absorbed by said liquid.

10. Apparatus as in claim 9 in which said first gas is ammonia, said second gas is hydrogen and said liquid is water.

11. Absorbtive heating and refrigerating apparatus, said apparatus comprising, in combination, a rotor, an annular water chamber in said rotor, an annular separator chamber surrounding said Water chamber, a first conduit leading from said water chamber into the outermost part of said separation chamber, an annular condenser chamber located radially inwardly from said water chamber, a second conduit extending from the innermost portion of said separation chamber to said condenser chamber, a first separator member extending radially in said separation chamber from its innermost wall to its outermost wall which blocks direct circumferential flow between the ends of said first and second conduits, an evaporation chamber extending axially from said water chamber, and communicating therewith, a third conduit extending axially from the outermost portion of said condenser chamber to near the axially most distant portion of said evaporation chamber, axially-spaced ridges on the inner surface of the outer wall of said evaporation chamber to hold liquid against axially-directed flow, a small water collection chamber enclosed within said condenser chamber, a fourth conduit extending from said water collection chamber to said water chamber, a second separator member extending radially from the outermost wall of said water chamber to a position located inwardly from the normal innermost rotational water level in said water chamber which blocks direct circumferential flow of liquid between the ends of said first and fourth conduits, said condenser chamber having a wall with heatdissipating fins extending therefrom, radial fins with plural peripherally-spaced holes extending from the outermost wall of said separation chamber, and fan-shaped fins ex- 1 tending from the outermost wall of said evaporation chamber.

12. A thermodynamic process, said process comprising the steps of rotating 2. gas and a gas-absorbing liquid in a rotary enclosure, guiding the flow of said liquid from a first station to a second station which is'at a radial distance from the axis of rotation of said rotary enclosure which is greater than the corresponding radial distance of said first station, driving a quantity of said gas out of said liquid at said second station and guiding said gas from said second station to a third station at a radial distance less than said radial distance of said second station, utilizing the flow of said gas between said second and third stations to transport said liquid out of said second station, guiding said liquid back to said first station, liquefying said gas at said third station and guiding the flow of the liquefied gas to a fourth station, evaporating the lastnamed liquid to re-form said gas at said first station and causing said gas to be absorbed into said first-named liquid.

13. An absorption refrigeration and heating process comprising the steps of absorbing a refrigerant in an absorbent fluid, applying centrifugal compressive forces to the resultant fluid, heating the latter to drive the refrigerant out in gaseous form, utilizing the gas bubbles formed during heating to transport the absorbent fluid opposite to the direction of the centrifugal force, cooling said gaseous refrigerant to liquefy it, adding heat to the liquefied refrigerant to evaporate it, and absorbing the resulting gas in said absorbent fluid.

(References on following page) 8 References Cited ROBERT A. OLEARY, Primary Examiner UNITED STATES PATE TS A. W. DAVIS, Assistant Examiner 1,315,282 9/1919 Carpenter 62-499X 2,197,001 4/1940 Maiuri 62---499X 2,724,953 11/1955 Justice 62499 5 624M499 

